activerecord: Fix where nil condition on composed_of attribute

1 files changed, 5 insertions, 4 deletions

diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb
index a0f6ada3ff..240de3bb69 100644
--- a/activerecord/lib/active_record/relation/predicate_builder.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder.rb
@@ -90,16 +90,17 @@ module ActiveRecord
             queries.reduce(&:or)
           elsif table.aggregated_with?(key)
             mapping = table.reflect_on_aggregation(key).mapping
-            if mapping.length == 1
+            values = value.nil? ? [nil] : Array.wrap(value)
+            if mapping.length == 1 || values.empty?
               column_name, aggr_attr = mapping.first
-              values = Array.wrap(value).map do |object|
+              values = values.map do |object|
                 object.respond_to?(aggr_attr) ? object.public_send(aggr_attr) : object
               end
               build(table.arel_attribute(column_name), values)
             else
-              queries = Array.wrap(value).map do |object|
+              queries = values.map do |object|
                 mapping.map do |field_attr, aggregate_attr|
-                  build(table.arel_attribute(field_attr), object.send(aggregate_attr))
+                  build(table.arel_attribute(field_attr), object.try!(aggregate_attr))
                 end.reduce(&:and)
               end
               queries.reduce(&:or)